Wall circuit breaker



Feb. 21, 1928. 1,659,614

F. w. ROLLER WALL CIRCUIT BREAKER Filed Sept. 25. 1924 2 Sheets-Sheet l 1 16' g 1 g g 1 25: 3- :02 :5 W 1 -20 8 1 1 5 1 104 I 3 0 '12 ii -15 11 a? pk a I y? 4 71 52' 8 jg INVENTOR ATTORNEYS I F. W. ROLLER WALL CIRCUIT BREAKER Filed Sept'. 25. 1924 Feb. 21, 1928.

2 Sheets-Sheet 2 INVENTOR Patented Feb- 21, 192s.

-- UNITED STATES PATENT OFFICE.

FRANK W. ROLLER, EAST ORANGE, NEW JERSEY, ASSIGNOR TO ROLLER-SMITH COMPANY, A CORPORATION OF NEW YORK.

VIALL CIRCUIT BREAKER.

Application filed September 25, 1924. Serial No. 739,752.

This invention relates to circuit breakers,

' and although some features are desirable in circuit breakers for various uses, the invention is particularly applicable to avall circuit breakers and to the formation of control panels for lighting and other circuits of rooms, oihces, residences and the like. a

One of the main objects of this invention is to provide a switch of the wall type which will be adapted to be easily inserted and removed from a receptacle, which receptacle may be'positioned in the wall beforethe plastering or finishing thereof and provided I with terminals to which the wiring circuits may be permanently connected. After the finishing of the wall, the only remaining step is to insert the circuit breaker mechanism into the box or receptacle and the switch is then ready for use. After installation, this invention has a further advantage that the mechanism may be readily removed for inspection, repair, or for changing adjust-- -ments, or replacement of parts or of the entire mechanism, 'as may be desirable when a different overload current value at which the circuit breaker trips is necessary; and this may be accomplished without disturbing the line wiring connections or other parts carried by the receptacle which may remain permanent.

Another important object of this invention is to provide a wall circuit breaker of the over-load type which will be simple and compact in construction and dependable in operation and adapted to be contained in a wall box' or wall receptacle and to be conveniently inserted and removed therefrom. An improvement of this character obviously makes it unnecessary to use fuses in the wiring circuits with the inconvenience of their removal and insertion when blown by overload. Another object of the invention is the provision in this type of circuit breaker, of

means whereby the circuit can not be closed and held closed by the operation of the circuit breaker handle when an overload or short .circuit condition exists; and by means of this improvement if a user moves the oper-- atinghandle to close the circuit breaker, it will be, automatically opened even though the operator holds the handle in position to closethe breaker. -Another object of the invention is to provide against the unnecessary opening of the breaker upon the occurrence of moderate -overload currents, unless they exist or continue for a certain interval of time. This avoids the inconvenience of having the circuit broken when the overload condition is transitory or not of sutiicient duration to be dangerous. These and other objects of this invention will be understood from the following description and accompanying drawings which illustrate a preferred embodiment thereof. A

Fig.1 is a front elevation of my improved circuit breaker shown in position on the wall; Fig. 2 is a vertical cross section on the line 22 of Fig. 1; Fig. 3 is a horizontal section on the line 33 of Fig. 2; Fig. 4 is a vertical section on the line 4e l of Fig. 2; Fig. 5 is a side view partly in section, showing the circuit breaker in open position; Fig. 6 is a similar view, showing the circuit breaker in open position with the locking linkage broken; and Fig. 7 is a diagrammatic view showing the circuits.

The breaker is contained within and protected by a casing 1 of metal or other suitable material which is located in an opening in the wall, this casing being positioned before finishing the wall. The outside casing is adapted to receive an insulating box 2 which carries the terminals of the wiring and is adapted to removably receive as a unit the circuit breaker mechanism. The outer portions of the four corners of the box 2 are cut away, as shown in Fig. 4;, to permit the convenient passing of the wires 3 from openings through the back of the box 1 and to the terminal screws 4. The incoming wires and terminals are the upper pair, the lower ones being the outgoing terminals and wires. Each of the upperterminals is at the end of a metal rod 5 which extends inwardly through supporting and insulating material and each rod 5 has extending downwardly from its inner end a terminal plate 6. The two plates thus form the fixed contacts of the breaker. From each of the lower terminals 4, a contacting rod, similar torod 5, extends inwardly through the insulating and supporting material, and has a contact plate 7 secured to its inner end and bent to extend outwardly in an opening8 at one side thereof. The two contact plates 7 are adapted to make electrical connection with corresponding contact plates 9 carried by the support for the circuit breaker mechanism, when the latter is slid into position in the box 2.

The box 2, being thus provided with terminals for the wiring and being provided with contacts engaged by the insertion of the switch mechanism, is adapted to be located in position before. the wall is finished and have the wiring permanently connected to the box terminals. Thus the wiring and box or receptacle for the switch mechanism may be installed, completed and tested at one time.

. The support for the switch mechanism is shown formed from a piece of sheet melzal having a main plate portion 10 with each upper and lower end bent inwardly and again bent at right angles so as to engage the projecting lips 1 of the box 1 and be removably secured thereto by the screws 10*. Portions of the plate 10 are bent inwardly in the form of two side strips 10 and have secured thereto on opposite sides thereof, the insulating plates 11 and 11 The inner end of the plate 11 has an upwardly extending block portion 11".

The main portion 10 of the supporting plate has two inwardly projecting central egs .10, one at each side. The manually operated switch handle element 12 is pivotally supported on the inner end of the right hand leg 10, having an inwardly extending portion 12, extending beyond the pivot of this element. At the'inner end of the portion 12 is a pin 12 which extends to the left, as shown in Fig. at. A spiral spring 13 is secured at one end to the end of the pin 12', the other end of the spring 13 being connected to the end of a pin 14, the pm 14 being mounted upon and fixed to the pivoted element 15. The element 15 IS in the form of a plate and is pivotally mounted on the inner end of the left hand leg 10, approximately in line with the axis of the operating element 12. The pin 14 is mounted on the element 15 in front of the 1 vot of the pivoted element -15 as shown in lgs. 2 and 3; and the relative movements of the parts are such that when the handle is moved from the position shown in Fig. 2

upwardly to the position shown in Fig. 5,

it will carry the line of action of spring 12 across the axis of the pivot of element 15 and cause the element 15, by tension of the spring, to be thrown from the position shown in Fig. 2 to that shown in Fig. 5. S1m1larly when the manual element is moved downwardly from the position shown in Fig. 5, it will carry the line of action of spring 12 across the axis of the element 15 and thereby cause the element 15 to be thrown to the position shown in Fig. 2. By

this action, the circuit breaker may be opened and closed manually by an abrupt snap action; giving aquick make and a quick break.

The' movable element'contacts 16 of the breaker are shown of yieldable form, being preferably made up of curved laminated strips. vEach of the contacts 16 is carried by a conducting element 16*, 16*, each of which is pivotally mounted at its lower end on the insulating part 11", at opposite sides of the block 11". The two conducting elements 16 are mechanically connected by an insulating bar or strip 16, as shown in Figs. 2, 3, 5 and 6, and as diagrammatically indicated in Fig. 7.

A U shaped element 17 is mounted on the outer face of the insulating element 16*, the element 17 having its two legs projectingl outwardly as shown in Fig. 3. The ro 17 extends horizontally through the outer ends of the element 17, being pivotally mounted therein. Afiixed to the rod 17" is an outwardly projecting arm 18, which arm is pivotally connected with one end of a link 18, the other end of this link being pivotally connected to an upwardly extending portion 15 of the pivoted element 15. The parts 18 and 18 form a'locking linkage of collapsible form. When these linkage pa rts are approximately in line, or have their middle ends slightly beyond a line passing through the axis ofthe pivots of the outer ends of the parts 18, 18*, they are locked in position and can not move much beyond this position owing to the link 18 having a tongue 18 which is bent over the top of the arm or link 18 and prevents the linkage from collapsing on one side of the line connecting the pivotsto their outer ends, but permits the collapse of the linkage inthe opposite direction. In Figs. 2 and 3, the locking linkage is shown in a locked position, whereas in Fig. 6, it is shown in collapsed position. A spiral spring 19 encircles the rod 17 and is connected at one end to the arm 18 and at its other end to one leg of the support 17 and thereby tends to turn thelockmg linkage to locked position. The movable contacts are biased to open position by the spring pressure of the contact brushes and any suitable means such as a wire or leaf spring 20, well shown in Figs. 5 and 6, which'is secured at its lower end to the block 11 and at its upper end bears on the inner side of the cross strip 16 and tends to throw the movable contacts outwardly to open position.

The controlling means for opening the circuit breaker automatically comprises a bimetallic thermostatic element 21 and in this instance is of U form as indicated in Fig. '7 and secured at the outer ends of its .arms

to the insulating part 11*, as shown in current, passes through the same for a predetermined time interval, depending upon the magnitude of the current, its raised end will be deflected downwardly and so release a trip and thereby cause the automatic opening of the circuit breaker.

Mounted on the block 11 and between the pivoted conducting elements 16 is a post 22 extending outwardly from the block 11 and pivotally carries at its end a lever 23. The lower end of this lever, when the circuit breaker is closed, normally engages the loop of the element 21, the upper end being con- '17 forming the downwardly extending arm 17 and is in the path of the pin 23 carried on the upper end of the lever 23. Thus when the arm 23 is automatically released and the spring 24 throws the pin 23 outwardly, the arm 17 will be turned clockwise, as well as the rod 17 which results in the arm 18 of the locking linkage being turned clock-wise. This will cause the collapse of the locking linkage and thereby cause the automatic opening or the breaker.

The circuit connections to the movable contacts of the breaker from the contacts 9 are obtained by means of screws 9 and 9 The screw 9 connects the left hand contact 9., shown'in Fig. 4:, directly with the left hand movable conducting element 16 through its support, or suitable yieldable or flexible leads. The screw 9' secures electrical conneotion from the other contact 9 to one of the outer ends of the element 21, the other end of this -element being electrically connected in any suitable manner to the right hand conducting strip 16*, the connections being indicated in Fig. 7.

As the position of the hand operating element does not necessarily indicate whether the breaker is closed, there is provided an indicator for this purpose. One of the ends of rod 17 a has pivotally connected. therewith, as shown in Figs. 2 and 3, the link 25, the outer end of this link being pivotally connected to an indicating element26. This element is pivotally mounted upon an arm 10 which arm extends inwardly from the plate 10. The indicator element carries a segmental face 26, on the face of which appear the words On and Off circumferentially spaced apart from eachother. A finished cover plate 27 is secured to the plate 10 by screws 27 and has a slotted opening 27 through which the handle element 12 extends. The plate 27 also has an opening 27 opposite the indicator plate; and when the circuit breaker is in closed position, the lower end of the indicator plate appears opposite theopening 27 c and bears the word On. This position is shown in Figs. 1 to 4. When the breaker is open, the link 25 will turn the indicator element 26 on its pivot so that the word Off, shown in Fig. 3, will then appear opposite the opening 27 of the cover plate, the position of the parts at that time being shown in Figs. 5 and 6.

In operation, the breaker when closed causes the parts to assume the position shown in Fig. 2 the handle 12 being down. lVhen the breaker is opened manually, the handle is moved to its upper position shown in Fig. 5. In this movement and when the handle 12 is raised from the position shown in Fig. 2, the inner end or the handle element will carry the inner end of spring 13 downwardly and cause its line of action to be carried below the pivot of element 15. When this occurs the spring 13 causes the element 15 to be quickly turned counter clock-wise, thereby throwing the locking linkage backward and likewise the movable contacting elements of the breaker, throwing them to open positions as shown in Fig. 5. This movement of the circuit breaker contacts causes the indicator to be turned as above described and indicate the Oliposition. The upward movement of the handle element causes the arm 12 thereof to be turned inwardly putting compression upon the spring 24 and turns the lever 23 clockwise to the position shown in Fig. 5.- When the breaker is manually moved to closed position from the position shown in Fig. 5, as the handle is moved downwardly the line of action of he spring 13 is carried above the pivot of element 15 and the tension of the spring 13 thereby causes the element 15 to be turned in a clockwise direction which throws the movable contact elements to the closed position as shown in Fig. 2, the indicator to the On position and places the spring 24 under tension so that the lever 23 engages the raised portion of the thermostatic element 21.

As regards the automatic opening, assuming the parts to be in the position shown in Fig. 2, an overload current will cause the thermostatic element 21 to be deflected downwardly until the lower end of the lever 23 is released from the element 21. The'spring 24 then being under tension, it will throw the upper end of lever 23 outwardly and cause the pin 23" to engage the arm 17 b and turn the same in a'clock-wise direct-ion which will break the locking linkage, as previously described. This permits the brush pressure and the spring 20 to throw the movable contacts of the circuit breaker to open position,

as shown in Fig. 6, the indicator being then moved, as previously described, to indicate through the opening 27 that the breaker is off, or in open position. When in this condition, the handle element remains in its lower position, as shown in Fig. 6. To again close the breaker it is necessary to first raise the handle to its upper position. This movement carries the line of action of spring 13 below the axis of the element 15 which results in the element 15 being turned in a counter clock-wise direction, throwing the link 18 outwardly giving an opportunity for thelocking linkage to assume locked position. The parts their take the position shown in Fig. 5. Also when the handle is moved to its upper position, the arm 12 is turned inwardly putting the spring 24 under compression and thus throwing the lever 23 to the position shown in Fig. 5, the lower end of the lever 23 being bevelled will pass over the raised end of element 21 and into the slot between the two arms of the thermostatic element. ,The breaker may now be closed by moving the handle to its lower position and the parts will then assume the position shown in Fig. 2 by the action already described. provided the element 21 has cooled sufliciently to assume its normal condition.

The plate 10 andparts carried thereby are adapted to be readily inserted in the box 2 and to assume a definite position therein when secured in place by the screws 10*. In order to more definitely position and guide the parts when the mechanism is inserted, the box is provided with undercut-projections 2* as shown in Fig. 4 and the insulating part 11 is adapted to serve as a guide and fit between these projections. This insures the contacts 9 properly sliding into engagement with the contacts 7 and likewise insures that all of the parts will assume their proper.,-position in relation to the box 2 and p nts carried thereby.

tis apparent that this improvementfulfills the object and pomess the. advantages already referred to herein and other advantages apparent to one skilled in the art. It will -be understood that this invention may be embodied in various forms of constructifon without departing from the scope there 0 I claim:

1. A wall circuit breaker comprising a receptacle adapted to be inserted in a wall, and a mechanism adapted to be inerted and removed as a unit from said receptacle, said mechanism comprising a movable switch element, a manually operated element, a-

locking linkage connecting'said element and contact, and means for automatically breakmg said linkage for causing the opening oi the breaker upon the occurrence of an over and a mechanism adapted to be inserted and removed as a unit from said receptacle, said mechanism comprising a manually operated element, a movable contact, means operatively connecting said element and contact, comprising a locking linkage, and means comprising a thermostatic element for automatically breaking said linkage for causing the opening of the circuit breaker upon the occurrence of an over-load current.

3. A wall "circuit breaker comprising a receptacle adapted to be inserted in the wall, a reciprocating pivoted manually operated element, a second pivoted element, a spring connecting said elements, the line of action of said spring being adapted to he carried across the pivot of said second element when said first named element is moved in each of its two directions, a movable contact element, a locking linkage connected to said contact element and said second element, and means for automatically breaking said looking linkage upon the occurrence of an overloadourrent.

4. A wall circuit breaker comprising a receptacle adapted to be inserted in a wall,

a reciprocatingpivoted manually operated element, a second pivoted element, a spring connecting said elements, the line of action of said spring being adapted to be carried across the pivot of said second element when said first named element is moved in each of its two directions, a movable contact element, a locking linkage connected to said contact element and said second element, and means comprising a thermostatic element for automatically breaking said locking linkage upon the occurrence of an over-load current.

5. A wall circuit breaker comprising a receptacle adapted to be inserted in a wall, a reciprocating pivoted manually operated element, asecond pivoted element, a spring connecting said elements, the line of action of said spring being adapted to be carried across the pivot of said second element when said first named element is moved in each of its twodirections, a movable contact element, a locking linkage connected to said contact element and said second element, means comprising a thermostatic element for automatically breaking said locking linkage upon the occurrence of an over-load current, a cover plate, and an indicator visible through said cover-plate for indicating the position of the movable contact element.

6. A wall circuit breaker comprising a reciprocating manually operated element,

"mechanism controlled thereby for closing and opening the breaker comprising a locking linkage, a thermostatic element, a lever normally restrained by said thermostatic ele ment, and means controlled by said lever when released from said element for breaking said linkage.

. -A circuit breaker comprising a reciprosecond pivoted element, a spring connecting I said elements and adapted by movement of said manually operated element to have its line of action carried across the pivot of said second element, a movable contact element,

two locking links connected between said contact element and said second element, a thermostatic element, a lever normally restrained by said thermostatic element, means controlled by movement of said manually operated element for moving said lever to its restrained position and forplacing said lever under tension when imrestrained position, and means controlled by the automatic release of said lever for breaking said locking linkage to cause said contact element to move to open position automatically.

8. A circuit breaker comprising ,ascreciproeating pivoted manually operated element, a second pivoted element, a spring connecting said elements and adapted by. movement of said manually operated element-to have its line of action carried acrossthe pivot of said second element, a movable contact element, two locking links connected between said contact element and said second element, a thermostatic element, a lever normally restrained by said thermostatic element, means controlled by movement of said manually operated element for moving said lever to its restrained position, means controlled by the automatic release of said lever. for breaking said locking linkage to cause said contact element to move to open position-automatically,

and an indicator coupled to said contact element for indicating its open and closed position.

9. A wall circuit breaker comprising a receptacle adapted to be insertedina wall, and a mechanism adapted to be inserted and removed as a unit from said receptacle, said mechanism comprising a contact element, a

manually operated element for moving said contact element in one direction to close said circuit breaker and means for causing said contact element to be moved in the opposite direction to open said circuit breaker upon the occurrence. of an abnormal circuit condition without disturbingthe position of said manually operated element.

10. A wall switch comprising a receptacle tacle having terminals to receive the wires and also having fixed contacts in said receptacle, a removable plate, a switch mechanism carried by said plate and adapted to be inserted as a unit with said plate from said receptacle, and contacts carried by said 'plate and adapted to engage certain of said first named contacts upon the insertion of said mechanism into said receptacle, said switch mechanism havingcontacts cooperating with other of said first named contacts to open the circuit upon occurrence of abnormal circuit conditions. Y

11. A wall switch comprising a receptacle adapted to be mounted in a wall, saiii receptacle having terminals to receive the wires and also having fixed contacts in said receptacle, a removable plate, a switch mechanism carried by said plate'and adapted to be inserted and removed as a unit with said plate from said receptacle, contacts carried by said plate and adapted to engage certain of said first named contacts upon the insertion of said mechanism into said receptacle, said switch mechanism having contacts movable in one direction to engage other of said first named contacts to close the circuit, and movable in the opposite'direction to open said circuit, and means for automatically moving said contacts .in said opposite directionto open said circuit upon the occurrence of abnormal circuit conditions.

12. In a wall circuit breaker, a movable contact biased to' open circuit position, a manually operated element for moving said contact, releasable 'means operativel connecting said elementand contact, a releasing device for said means adapted to occupy a non-releasing position-and to be moved upon the occurrenceof abnormal circuit conditions ing position.

. FRANK W. ROLLER. 

